Answer:
B) decreases GDP by $60,000.
Step-by-step explanation:
The GDP includes the total production of final and legal goods and services. But in order for a service to be included in the GDP, they must be sold to someone else. The same restriction applies to a person that grows vegetables and fruits on his/her backyard for personal consumption.
If an exchange is not made, then it is not included in the GDP. The difference with manufactured products that once finished are included in inventories (increase investment) is that materials, labor and other inputs were used to produce them and someone got paid for them.